At Bouygues Energies & Services, a subsidiary of Bouygues Construction, the drone is used to check the state of photovoltaic farms and railway lines, to inspect pylons and high-voltage power lines, to conduct heating performance tests of buildings, to carry out topographical surveys, and even to monitor construction sites. Drones are certainly practical. But in our line of business, there is a less-developed use that deserves recognition.
Against the current
There are two standard ways of installing high-voltage cables: you can use either a tractor or a helicopter. The first is a simple solution but has a few drawbacks nonetheless; it is time-consuming as the cables have to be manually mounted on each pylon. The use of this solution also depends heavily on the topography of the terrain and on access to the pylons, particularly on farmland or in protected areas.
The second solution, the helicopter, is fast. The cable is lowered onto the pylon from above and an engineer catches it. That said, it is (very) expensive, not at all ecological and unpleasant for the engineers or neighbouring residents and farmers.
So the best alternative is the drone! It is easy, practical, cheaper and has a low ecological impact (in terms of noise, fuel, wind, etc.).
Bouygues Energies & Services is the first company in France to have developed the use of drones for unrolling cables. In practice, the drone is remote-controlled from the ground to fly over the pylons and drop the cables into the hands of the engineer who is positioned on top of the pylon. The engineer takes hold of the cable and runs it through a specific pulley. This continues from pylon to pylon. The next cables are then pulled until they reach the final high-voltage cable.
The drone is particularly useful on uneven ground; it is two to three times faster and there is no comparison in terms of environmental protection!
Manager of the drones activity at Bouygues Energies & Services